/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution
{
public:
    ListNode *getKthFromEnd(ListNode *head, int k)
    {
        ListNode *fast = head;
        ListNode *slow = head;
        while (k--)
        {
            fast = fast->next;
        }

        while (fast)
        {
            fast = fast->next;
            slow = slow->next;
        }
        return slow;
    }
};